In a packet network, a scheme must be implemented to avoid congestion. A simple solution would be to over-engineer the network such that congestion is not a problem. While this will serve to alleviate congestion, it can be very expensive and is often a short-term solution at best, as additional traffic growth can quickly overwhelm the network. Other solutions are typically network based and fall under the categories of bandwidth and traffic management. An example of traffic management would be routing packets over an alternate path in the network to avoid network elements that are experiencing congestion. An example of bandwidth management would be the network negotiating with an end user during session setup such that the bandwidth allocated to the end user will not exceed a given value and will not negatively affect already established sessions.
A brief discussion of network bandwidth management for three popular representative multimedia packet protocols is presented below. The protocols are: H.323 Packet-Based Multimedia Communications Systems, Session Initiation Protocol (SIP), and Asynchronous Transfer Mote (ATM).